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v3.25.3

Common stock - Narrative (Detail) | 9 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2025 USD ($) Vote shares | Dec. 31, 2024 shares | Sep. 30, 2024
Class of Stock [Line Items] |  |  |
Preferred Stock, shares authorized | 1,000,000 |  |
Preferred Stock, shares issued | 0 |  |
Economic equivalent of Class B share to Class A share | 0.0667% |  | 0.0667%
Share repurchases | 0 |  |
Common Stock Repurchase Program [Member] |  |  |
Class of Stock [Line Items] |  |  |
Shares repurchase, authorization description | Berkshire’s common stock repurchase program permits Berkshire to repurchase its shares any time that Warren Buffett, Berkshire’s Chairman of the Board and Chief Executive Officer, believes that the repurchase price is below Berkshire’s intrinsic value, conservatively determined. |  |
Minimum cash, cash equivalents and U.S. Treasury Bill threshold after repurchase of common stock shares, amount | $ | $ 30,000,000,000 |  |
Class A [Member] |  |  |
Class of Stock [Line Items] |  |  |
Number of votes entitled per share, number | Vote | 1 |  |
Shares outstanding | 523,424 | 547,562 |
Class B [Member] |  |  |
Class of Stock [Line Items] |  |  |
Number of votes entitled per share, number | Vote | 0.0001 |  |
Number of shares of Class B stock obtainable from converting one Class A share | 1,500 |  |
Shares outstanding | 1,372,199,139 | 1,335,992,139 |
Equivalent Class A [Member] |  |  |
Class of Stock [Line Items] |  |  |
Shares outstanding | 1,438,223 | 1,438,223 |

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